Liam Neeson is a gentle, hulking, and lovable action hero.

Still from Unknown. Click image to expand.

Unknown (Warner Bros.) wants to be a spy thriller in the Bourne mode: a semi-amnesiac hero, a shadowy international organization, intricately choreographed chases through a chilly European capital. Granted, this is cut-rate Bourne, as befits a late February release. The stunts are a shade less spectacular, the hero’s existential puzzlement less deftly sketched, the plot less … sense-making. But if you dig Liam Neeson as an action hero (remember him in 2008’s Taken, as the devoted assassin dad who kicked Albanian-gangster * ass to rescue his daughter from sex slavery?), you could do worse than this fast-paced, cheerfully ridiculous, generally satisfying romp.

The botanist Dr. Martin Harris (Neeson) and his wife Liz (January Jones) have just arrived in Berlin for a biotechnology summit. They’re about to check into their hotel when Martin realizes that he’s left his briefcase at the airport. He jumps in a cab to go and get it—and is promptly involved in a near-fatal car crash. Four days later he awakes from a coma in the hospital, with no identification and no memory of the accident. Martin remembers who he is, though some of the details are blurry—but no one else seems to. When he returns to the hotel, his wife treats him like a stranger. Weirder still, Liz is now staying at the hotel with a man (Aidan Quinn) who claims to be Dr. Martin Harris, and has the papers to prove it. Martin’s protestations that there must be some kind of plot against him only brand him as a lunatic, and he’s escorted out by hotel security.

With no ID and only a few euros in cash, Martin wanders the streets of Berlin looking for the taxi driver who saved his life after the crash, Gina (Diane Kruger), an illegal Bosnian refugee who has nicer cheekbones than your average cabbie. At first, Gina distrusts this seemingly deranged American, but after they’re attacked by a pair of hired thugs on a mission to kill them both, she starts to take his story seriously. As the two of them team up to investigate, Martin begins to doubt his own identity: Is it possible, as his doctor insists, all this confusion has been brought on by the head injury? Was he ever really Martin Harris at all?

Until a last-act twist that sacrifices plausibility on the altar of surprise, this is an economical thriller with some nice directorial touches, including a use of subjective camera that captures the disorienting experience of regaining consciousness in a hospital. A few vertiginous moments in the first third almost recall such great identity-switching dramas as Hitchcock’s North by Northwest or John Frankenheimer’s Seconds. The director,Jaume Collet-Serra( House of Wax, Orphan),does a fine job painting his hero into an epistemological corner, but he’s not as skillful at getting him out again. I can’t say much more without revealing the twist, but when Martin finally figures out the reason no one’s recognizing him, he’s not the only one who’s befuddled. The character soon recovers his senses and gets back to chasing bad guys, but the audience spends the remaining third of the movie in an extended “Huh?”

The venerable German actor Bruno Ganz plays a former Stasi agent whom Martin hires to help him prove his identity, and Frank Langella has a brief and marvelous small part as an American professor whom Martin contacts for help. The one scene that Ganz and Langella have together is worth the price of admission. Both are actors capable of elevating whatever material they’re in, and for a few moments this fair-to-middling spy drama feels as emotionally rich and morally ambiguous as a Graham Greene novel.

I don’t watch Mad Men, but I’m aware of the ongoing debate over whether or not January Jones can act. Based on this movie, my response would be no, but her blankness is a good fit for her slippery character: Is Liz pretending not to recognize her husband, or has she been brainwashed into forgetting him? Diane Kruger is tolerably good, if miscast, as the improbably gorgeous Bosnian cabbie. But it’s Neeson’s irreducible menschiness that holds the whole jury-rigged construction together. As an action hero, Neeson has a way of coming off as both invincible and tender; he’s capable of hurling a man off an eight-story parking structure, but he’ll only do it for the sake of someone he loves. The script doesn’t need to fill in every hole when it comes to Martin Harris’s true identity: He’s embodied by this gentle, hulking hero, and we’re on his side.

Correction, Feb. 22, 2011: The article originally misidentified the gangsters in Taken as Russian, not Albanian. (Return to the corrected sentence.)

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